Technology offers the consumer many choices in communications hardware, allowing both data and voice transmission. These choices include portable computers with internal modems, hands-free speakerphones, landline telephones, and cellular telephones.
Modern portable computers may be equipped with an internal modem and data access arrangement that allows the internal modem to be connected through an RJ-11 connector to the Public Switched Telephone Network. Examples of this technology include portable computers manufactured by Zenith and NEC. These portable computers generally include a speaker used for call progress monitoring; and this speaker is used strictly as an analog output device. The internal modems are used only for sending and receiving modulated digital information through the public switched telephone network. Methods of modulation include the Bell 212, Bell 103 CCITT V.21, CCITT V.22 and CCITT v.22 bis standards.
Hands-free speakerphones can be found in many offices and homes. Generally, these speakerphones are used as an adjunct to a classical telephone which consists of a cradle and handset, and these speakerphones are used for analog voice communications over the public switched telephone network. Digital switching techniques are sometimes used within the speaker phone circuits to prevent analog feedback from microphone pickup of the speaker output.
Cellular telephones as currently manufactured by Motorola (USA), OKI (Japan) and others consist of a radio transceiver unit (TRU) and a control unit (CU), analogous to the cradle and handset of a conventional landline telephone. The transceiver unit is connected to the control unit with numerous wires, these wires transferring the analog information as in a conventional landline telephone, and also transferring digital information not used in a conventional landline telephone. This digital information may contain key press, display, and monitoring information, as well as cellular call set-up instructions. An example of this digital and analog connection can be found in AMPS based cellular telephones, as well as other functionally similar specifications. A complete description of the AMPS system is provided in xe2x80x9cThe Bell System Technical Journalxe2x80x9d, 1979, V.1 58, No. 1, pages 1-269. Cellular phones may also provide a hands-free speakerphone, similar to speakerphones available for landline phones.
Landline and cellular telephones generally provide means of indicating to the user their current operating state. For example, when a key is pressed, an audible tone is heard, providing audio feedback, or, when an incoming call is sensed, an audible tone (RING) is heard.
There have been attempts in the prior art to combine some of the devices described above. For example, the addition of a modem to a cellular phone and means for controlling a cellular phone was disclosed by the present inventor in his U.S. Pat. No. 4,697,281. Although this patent provides for modem, transceiver unit and control unit analog and digital control, it does not provide a method for connecting numerous communication devices selectively to both land line and cellular telephone networks.
U.S. Pat. No. 4,718,080 shows a device which connects a standard landline telephone or modem to a cellular car phone, while U.S. Pat. No. 4,578,537 shows an interface which may connect a personal computer, a speakerphone, and a modem to one or more landlines. As a final example, U.S. Pat. No. 4,685,123 teaches a method of adapting one or more telephone lines for either data or voice communications.
None of these known devices or methods succeeds in achieving the functionality ultimately possible from the combination of a modem, portable computer, cellular phone, speakerphone, headset, and landline connection. Were these devices combined within a compact, portable package, the user could use the computer, transmit data, and/or place a cellular voice call, using speakerphone or headset, from any location served by a cellular network. Further, the user could bring the unit into home or office and connect it to the public switched telephone network. With both cellular and landline connections available, the user could place two calls at once, transmitting voice or data over either line. Significantly, the portable computer could initiate all these operations under program control. If all these devices could be combined in an integrated unit so that any pair of devices could function together, the result would be an uniquely valuable business and personal tool.
Prior to the invention disclosed herein, this combination was not conceived of in the art for a number of reasons, but primarily because the devices described were considered to be incompatible. For example, as explained in the inventor""s prior U.S. Pat. No. 4,697,281, an ordinary modem loses data during cell handoffs, when operated over a cellular link. As another example, ordinary telephones do not provide the correct control signals to place calls on the cellular network, and cellular control units cannot be used as landline handsets. Thus, an integrated portable unit which combines a personal computer, cellular transmitter, modem and speaker phone with headset, cellular control unit, and land telephone connections could not be implemented by merely wiring known devices together.
It is a primary object of the present invention to provide a novel and improved portable hybrid communication system incorporating an integrated, portable unit which includes a personal computer, cellular transmitter, modem, and speakerphone, and which has external connections for a headset, cellular control unit, and land telephone line, such that any of these devices may be used with any other device. The invention further includes a novel and improved method and apparatus to switch the numerous analog and digital parts of landline telephones, cellular telephones and modems so that any parts of this unit may be used together. This is all accomplished with a control system mounted on a circuit card which fits in a modem slot or similar card receiving slot in a portable computer.
Another object of the present invention is to provide a novel and improved portable hybrid communication system which provides a personal computer with the means to command a specific pairing of a cellular transmitter, modem, and speakerphone, as well as external connections to a headset, cellular control unit and landline telephone line. This command may be sent by an automated program, or at the interactive request of the person using the personal computer.
Yet another object of the present invention is to provide a novel and improved portable hybrid communication system which can switch a modem onto either a landline or cellular telephone network.
A further object of the present invention is to provide a novel and improved portable hybrid communication system which controls the power to a cellular control unit as necessary, so that power to the control unit is available only when the control unit is to be used.
Yet another object of the present invention is to provide a novel and improved portable hybrid communication system which can sense the ON or OFF condition of the power to a transceiver unit.
A further object of the present invention is to provide a novel portable hybrid communication system which has complete control of a transceiver unit, providing the necessary signals to the transceiver unit for the transceiver unit to function properly, and sensing all of the signals generated by the transceiver unit, said control being possible without the need of a cellular control unit.
Yet another object of the present invention is to provide a novel portable hybrid communication system with complete control of a cellular control unit, providing the necessary signals to the control unit for the control unit to function properly, and sensing all of the signals generated by the control unit, allowing use of the cellular control unit.
A further object of the present invention is to provide a novel portable hybrid communication system that can sense whether of not a headset, cellular control unit, landline, or other device is connected to the invention.
A further object of the invention is to provide a novel portable hybrid communication system that selectively provides suitable control signals and data transfer protocols depending on the devices used and depending on whether cellular or land lines are being used.
A further object of the invention is to provide a novel portable hybrid communication control system that performs analog signal conditioning so that the analog signals of the speakerphone, headset, control unit, modem, tone generator, transceiver, and landline are matched in impedance and level according to definite standards.
A further object of the invention is to provide a novel portable hybrid communication system that can relay a cellular call over a land line or a land line call over a cellular network.
A further object of the invention is to provide a novel portable hybrid communication system that can simultaneously connect a modem or voice terminal device to the cellular network, while connecting another device (modem or terminal) to a landline, permitting simultaneous voice and data communications.
A further object of the invention is to provide a novel portable hybrid communication system which integrates a modem, portable computer, and cellular transmitter into a case, the case having a retractable cellular antenna.
These objects and others are achieved by providing a novel and improved portable hybrid communication system which is a laptop device including a personal computer, a cellular transceiver, a speakerphone, and a hybrid communications control unit. The device has connectors for attaching a headset, cellular control unit, land telephone line, and additional speakers and microphones.
The hybrid communications control unit is microprocessor controlled and includes a modem, a data access arrangement, and a tone generator as well as digital, analog, and power switches. The hybrid communications control unit switches the communications components and provides, under program control, the proper protocols, level, and impedance matching to connect the modem, speakerphone, headset, speaker/-microphone, or cellular control unit to the landline or to the cellular network via the transceiver.
Matching and switching operations are automatic and transparent to the user. The unit can also connect two of the terminal devices or connect the cellular and landlines for call relaying. Finally, the device is capable of connecting plural calls at the same time over different networks.
The hybrid communications control unit may be controlled by its internal firmware, by toggle switches, or by commands issued from the personal computer.
Other objects and advantages of the invention will be apparent to those skilled in the art from the drawings, description, and claims herein.